Before you can learn what NetBEUI is, you must first know what NetBIOS is.
NetBIOS stands for Network Basic Input/Output System, and it's the system that offers services connected to the session layer of the OSI model that enables programs on two separate computers to communicate with each other over a LAN or local area network.
In turn, NetBEUI is essentially an enhanced version of NetBIOS, its name standing for NetBIOS Extended User Interface (or, if you want to be really technical about it, it stands for Network Basic Input/Output System Extended User Interface).
It's also known y the name NetBIOS frame (NBF) protocol thanks to its frame format formalization. Because NetBEUI is an improved kind of NetBIOS, it is also by default strictly an API and does not serve as a networking protocol.
NetBIOS runs on older operating systems such IPX/SPX and IEEE 802.2 using the NetBIOS over IPX/SPX or NBX and the NBF or NetBIOS Frames protocols.
Modern networks that run NetBIOS over TCP/IP do so via the TCP/IP (NBT) protocol, which causes every computer connected to the network to sport both a NetBIOS name corresponding to a (possibly different) host name and an IP address.
Network operating systems at present use NetBEUI for their software network communication needs, and they include such systems as Windows NT, Windows 95, LAN Server, LAN Manager, and Windows for Workgroups.
The NetBEUI protocol was first developed by IBM for use with their LAN Manager server.
It eventually gained compatibility with Novell- and Microsoft-brand servers as time passed by. DEC and Hewlett-Packard also use the NetBEUI format in their respective network operating systems as well.
The main difference between NetBIOS and NetBEUI is the fact that the latter formalizes the frame format that wasn't indicated as part of the original NetBIOS (the frame format of course refers to how information is arranged in a given data delivery or transmission).
This newer, extended version of NetBIOS does its function by offering the following distinct NetBIOS services: datagram distribution service for connection less communication, session service for connection-based communication, and name service for name registration and resolution.
NetBEUI functions at the Network and Transport layers of your LAN.
Furthermore, this protocol serves as the interface of choice for single-LAN communication.
When it comes to clear-cut transmission of information and communication within a single LAN, NetBEUI is the superior choice because it's the next evolution of the reliable, tried-and-true NetBIOS format.
Then again, it also has the NetBIOS limitation of not being able to route messages to other networks, so you'll have to adapt its interface to other protocols like TCP/IP or the Internet Protocol Suite and IPX or the Internet work Packet Exchange.
Adaptation is required and unavoidable when it comes to internetwork routing.
It's recommended that you first install both TCP/IP and NetBEUI in each of the computers connected to the network and setup the server to utilize NetBEUI for communication purposes within the LAN while using TCP/IP for outside LAN communication.